the first huge and striking problem with Barr’s memo is that he unjustifiably makes countless assumptions about what Mueller is doing; about Mueller’s purported “theory” of presidential criminal culpability; about Mueller’s “sweeping” and “all-encompassing” “interpretation” of the statute and Constitution; about “Mueller’s core premise[s]”; . . . about “unprecedented” steps Mueller is proposing to take; about “Mueller’s proposed regime”; about “Mueller’s immediate target”; about Mueller’s presumed failure to “provide a standard” for what constitutes “corruptly” trying to impede proceedings; about Mueller’s “demands” that the President submit to interrogation; etc.To read this memo, you’d think Barr were replying to a legal brief that Mueller had submitted in support of a prosecution of the President for obstruction of a federal proceeding. Yet as Barr concedes at the outset, he was “in the dark about many facts.” Indeed, he presumably was “in the dark” about virtually everything he wrote about. From all that appears, Barr was simply conjuring from whole cloth a preposterously long set of assumptions about how Special Counsel Mueller was adopting extreme and unprecedented-within-DOJ views about every pertinent question and investigatory decision—and that Deputy Attorney General Rosenstein was allowing him to do so, despite the fact that Mueller is required to “comply with the rules, regulations, procedures, practices and policies of the Department of Justice” and to “consult with appropriate offices within the Department for guidance with respect to established practices, policies and procedures of the Department.”